JP2018182310A - Method of processing an object - Google Patents

Abstract

Provided is a technique for forming a film on an object to be processed in a region-selective manner with good controllability. A method according to an embodiment generates a plasma of a first gas in a processing container in which an object to be processed is accommodated to change an etching target layer of the object to be processed through an opening of the object to be processed. Etching step, and after this step, a first step of supplying a second gas into the processing vessel, a second step of purging the space in the processing vessel, and oxygen atoms in the processing vessel. Including a step of repeatedly executing a sequence including a third step of generating plasma of a third gas including and a fourth step of purging a space in the processing container to form a film on the inner surface of the opening, The gas contains carbon atoms and fluorine atoms, the second gas contains an aminosilane-based gas, the etching target layer is a hydrophilic insulating layer containing silicon, and the first step generates plasma of the first gas. do not do. [Selection] Figure 1

Description

Embodiments of the present disclosure relate to a method of processing an object.

In the process of manufacturing an electronic device, a mask is formed on a layer to be treated, and etching is performed to transfer the pattern of the mask to the layer to be treated. Patent Document 1 discloses a technique for improving the shape of holes of a pattern generated by etching. Patent Document 2 discloses a technique aimed at forming well patterns on a substrate by an etching process and a film forming process. Patent Document 3 discloses a technique of cyclically performing etching while forming a protective film of a mask.

International Publication No. WO 2014/046083 Brochure JP, 2014-17438, A JP 2006-523030 A

There is a need for a technique for forming a film selectively on a target object with good controllability.

In one aspect, a method of processing an object is provided. The object to be processed includes a layer to be etched and a mask provided on the layer to be etched. An opening is formed in the mask up to the layer to be etched. The method for treating the object comprises the steps of anisotropically etching the layer to be etched through the opening (hereinafter referred to as step a) and forming a film on the inner surface of the opening after the step a is performed. (Hereinafter referred to as step b). In step a, plasma of a first gas is generated in a processing container of a plasma processing apparatus in which an object to be processed is accommodated. Step b includes a first step of supplying a second gas into the processing container, a second step of purging a space in the processing container after the execution of the first step, and oxygen in the processing container after the execution of the second step A sequence including a third step of generating a plasma of a third gas containing atoms and a fourth step of purging a space in the processing container after the execution of the third step is repeatedly performed on the inner surface of the opening Form a film. The first gas comprises carbon and fluorine atoms. The second gas contains an organic-containing aminosilane-based gas. The layer to be etched is a hydrophilic insulating layer containing silicon. The first step does not generate plasma of the first gas.

The etching performed in step a causes the deposition portion, which is a reaction product resulting from the first gas, to be attached to the opening, and a portion of the inner surface of the opening to which the deposition portion is not attached (the etching layer is exposed) In some cases, a bowing shape (dent) may be formed on the According to the method of the one aspect, the step b performed after the step a removes the deposited portion attached to the opening and forms the film on the portion where the bowing shape is formed. The bowing shape can be relaxed by

In one embodiment, in the first step, the etching target layer is etched through the opening while adjusting the temperature of the processing target to be uniform over a plurality of regions of the processing target. In the first step using the second gas, a chemical reaction is used without generating plasma, so the thickness of the film formed in step b including the first step is the thickness of the film on which the film is to be formed. It increases as the temperature of the treatment body (particularly the layer to be etched) rises. Therefore, according to the method according to the present embodiment, the thickness of the film formed in step b may be uniform over a plurality of regions of the object to be treated.

In one embodiment, the processing vessel is provided with a first gas inlet and a second gas inlet. The first gas inlet is provided above the object to be treated. The second gas inlet is provided on the side of the object to be treated. In step a, the first gas is supplied into the processing container from the first gas inlet, and the backflow preventing gas is supplied into the processing container from the second gas inlet. The first step of step b supplies the second gas into the processing vessel from the second gas inlet and supplies the backflow prevention gas into the processing vessel from the first gas inlet. In the third step b, the third gas is supplied into the processing container from the first gas inlet, and the backflow prevention gas is supplied into the processing container from the second gas inlet. The pipe connected to the first gas inlet and the pipe connected to the second gas inlet do not intersect with each other. According to the method according to the present embodiment, a second gas inlet for introducing a second gas containing a relatively reactive organic-containing aminosilane gas used in the first step into the processing container, and , The first gas inlet used to introduce the first gas containing carbon atoms and fluorine atoms in the step a and the third gas containing oxygen atoms used in the third step are different from each other. Since the gas supply pipe connected to the first gas inlet and the gas supply pipe connected to the second gas inlet do not intersect with each other, a relatively reactive organic-containing aminosilane-based gas The reaction products that can be generated in the gas supply pipe can be reduced due to the second gas containing H, and the first and third gases. In addition, by using the backflow prevention gas, the first gas, the second gas, and the third gas can be supplied to the gas supply pipe in a state where none of the first gas, the second gas, and the third gas is flowing. Backflow of any of the gases can be avoided.

In one embodiment, the first gas comprises a fluorocarbon-based gas. In this manner, etching can be performed on the layer to be etched, which is a hydrophilic insulating layer containing silicon, using the first gas containing a fluorocarbon gas in the step a.

In one embodiment, the second gas comprises monoaminosilane. Thus, the formation of the silicon reaction precursor can be performed in the first step using the second gas containing monoaminosilane.

In one embodiment, the aminosilane-based gas contained in the second gas comprises an aminosilane having 1 to 3 silicon atoms. The aminosilane-based gas contained in the second gas contains aminosilane having 1 to 3 amino groups. Thus, an aminosilane having 1 to 3 silicon atoms can be used as the aminosilane-based gas contained in the second gas. Further, as the aminosilane-based gas contained in the second gas, aminosilane having 1 to 3 amino groups can be used.

In one aspect, a method of processing an object is provided. This method comprises the steps of: forming a first film selectively on the surface of the object; and forming a second film by atomic layer deposition on the surface of the object while removing the first film. .

In one embodiment, the deposition includes a first step of supplying a second gas into the processing container to form an adsorption layer on the surface of the object, and a second step of purging a space in the processing container. And a third step of generating a plasma of a third gas in the processing container.

In one embodiment, the depositing further comprises a fourth step of exposing the second film to a plasma of inert gas after the third step.

In one embodiment, in the step of forming the second film, the first film is removed in the third step or the fourth step.

In one embodiment, the second gas is an aminosilane gas, a gas containing silicon, a gas containing titanium, a gas containing hafnium, a gas containing tantalum, a gas containing zirconium, a gas containing organic matter The third gas is any of a gas containing oxygen, a gas containing nitrogen, or a gas containing hydrogen.

In one embodiment, the first film is formed by plasma etching.

In one embodiment, the plasma etch is an atomic layer etch.

In one aspect, a method of processing an object is provided. This method comprises the steps of: preparing an object having a first region made of a first material and a second region made of a second material different from the first material; And forming a first film on the second region, and forming a second film by atomic layer deposition on the first region while removing the first film.

In one embodiment, the first gas comprises a fluorocarbon gas, the first material comprises silicon, and oxygen, and the second material comprises any of silicon, organic or metal.

In one embodiment, the first gas comprises fluorohydrocarbon gas, the first material comprises any of silicon, organic or metal, and the second material comprises silicon and nitrogen.

In one embodiment, the second film contains silicon.

In one embodiment, the second film formed on the object has a plurality of film thicknesses.

In one embodiment, the first film is removed by repeating the sequence, and the second film is formed on the removed object surface.

As described above, there is provided a technique for forming a film on an object to be processed selectively with good controllability.

FIG. 1 is a flow chart illustrating a method of processing an object according to one embodiment. FIG. 2 is a view showing an example of a plasma processing apparatus that can be equipped with the processing system shown in FIG. FIG. 3: is a figure which shows typically a part of several area | region of the main surface of the to-be-processed object divided in the method of processing the to-be-processed object which concerns on one Embodiment as an example. 4 includes (a), (b) and (c), and (a) of FIG. 4 is a cross-sectional view showing the state of the object to be processed before the process shown in FIG. FIG. 4 (b) is a cross-sectional view showing the state of the object to be processed after the execution of etching shown in FIG. 1, and FIG. 4 (c) is the object to be processed after execution of multiple sequences shown in FIG. It is sectional drawing which shows the state of. FIG. 5 is a view showing the state of supply of gas and supply of high frequency power during execution of each step of the method shown in FIG. 6 includes (a), (b), and (c), and (a) of FIG. 6 is a diagram schematically showing the state of the object before execution of the sequence shown in FIG. 1, for example. 6 (b) schematically shows the state of the object being processed during execution of the sequence shown in FIG. 1, and FIG. 6 (c) shows the state after execution of the sequence shown in FIG. It is a figure which shows the state of a to-be-processed object typically. FIG. 7 is another flowchart showing a method of processing an object according to an embodiment. FIG. 8 is a view schematically showing the formation of a film on the surface of the object according to the method shown in the flow chart of FIG. 7 including (a) and (b). FIG. 9 schematically shows the etching and formation of a film according to the method shown in the flow chart of FIG. 7 comprising (a) and (b). FIG. 10 is a view showing how the film thickness is changed by the execution of the method shown in the flow chart of FIG. 7. FIG. 11 is a diagram showing a change in film thickness according to the method shown in the flow chart of FIG.

Hereinafter, various embodiments will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

First Embodiment
When a film to be etched is etched using a mask that defines a pattern shape, reaction products are deposited on the inner surface of the opening (the opening of the mask) as the etching progresses. For this reason, necking may occur in which the opening is blocked by the deposition of reaction products. When the deposition portion of the reaction product is formed in the opening, the collision of ions in the plasma with the deposition portion bends the traveling direction of the ions and loses the anisotropy. Therefore, ions may collide with the inner side of the opening, and a bowing shape may be formed on the side. When the bowing shape becomes noticeable, the inside of two adjacent openings can penetrate. Therefore, a technique for reducing the bowing shape of the inner surface of the opening that may be generated by etching is desired. The first embodiment provides a technique for reducing the bowing shape of the inner side of the opening that may be produced by etching.

FIG. 1 is a flow chart showing a method of processing an object to be processed (hereinafter sometimes referred to as a wafer W) according to an embodiment. The method MT shown in FIG. 1 is an embodiment of a method of processing an object. The method MT (a method of processing an object to be processed) is performed by the plasma processing apparatus 10.

FIG. 2 is a diagram showing an example of a plasma processing apparatus according to an embodiment used to execute the method MT shown in FIG. FIG. 2 schematically shows the cross-sectional structure of the plasma processing apparatus 10 that can be used in various embodiments of the method MT. As shown in FIG. 2, the plasma processing apparatus 10 is a plasma etching apparatus provided with parallel plate electrodes, and is provided with a processing container 12. The processing container 12 has a substantially cylindrical shape and defines a processing space Sp. The processing container 12 is made of, for example, aluminum, and the inner wall surface thereof is anodized. The processing container 12 is grounded for security.

A substantially cylindrical support 14 is provided on the bottom of the processing container 12. The support portion 14 is made of, for example, an insulating material. The insulating material constituting the support portion 14 may contain oxygen like quartz. The support portion 14 extends in the vertical direction from the bottom of the processing container 12 in the processing container 12. A mounting table PD is provided in the processing container 12. The mounting table PD is supported by the support portion 14.

The mounting table PD holds the wafer W on the upper surface of the mounting table PD. The main surface FW of the wafer W is on the opposite side of the back surface of the wafer W in contact with the upper surface of the mounting table PD, and faces the upper electrode 30. The mounting table PD has a lower electrode LE and an electrostatic chuck ESC. The lower electrode LE includes a first plate 18a and a second plate 18b. The first plate 18a and the second plate 18b are made of metal such as aluminum, for example, and have a substantially disc shape. The second plate 18 b is provided on the first plate 18 a and is electrically connected to the first plate 18 a.

An electrostatic chuck ESC is provided on the second plate 18b. The electrostatic chuck ESC has a structure in which an electrode which is a conductive film is disposed between a pair of insulating layers or between a pair of insulating sheets. A DC power supply 22 is electrically connected to the electrode of the electrostatic chuck ESC via a switch 23. The wafer W is in contact with the electrostatic chuck ESC when being mounted on the mounting table PD. The back surface of wafer W (surface opposite to main surface FW) is in contact with electrostatic chuck ESC. The electrostatic chuck ESC adsorbs the wafer W by electrostatic force such as coulomb force generated by the DC voltage from the DC power supply 22. Thereby, the electrostatic chuck ESC can hold the wafer W.

A focus ring FR is disposed on the peripheral portion of the second plate 18b so as to surround the edge of the wafer W and the electrostatic chuck ESC. The focus ring FR is provided to improve the uniformity of etching. The focus ring FR is made of a material appropriately selected depending on the material of the film to be etched, and may be made of, for example, quartz.

A refrigerant channel 24 is provided inside the second plate 18 b. The refrigerant channel 24 constitutes a temperature control mechanism. A refrigerant is supplied to the refrigerant flow path 24 from a chiller unit (not shown) provided outside the processing container 12 through a pipe 26 a. The refrigerant supplied to the refrigerant channel 24 is returned to the chiller unit through the pipe 26b. As described above, the refrigerant is supplied to the refrigerant channel 24 so as to circulate. By controlling the temperature of the refrigerant, the temperature of the wafer W supported by the electrostatic chuck ESC can be controlled.

The plasma processing apparatus 10 is provided with a gas supply line 28. The gas supply line 28 supplies the heat transfer gas from the heat transfer gas supply mechanism, for example, He gas, between the upper surface of the electrostatic chuck ESC and the back surface of the wafer W.

The plasma processing apparatus 10 is provided with a temperature control unit HT that controls the temperature of the wafer W. The temperature control unit HT is built in the electrostatic chuck ESC. A heater power supply HP is connected to the temperature control unit HT. By supplying power from the heater power supply HP to the temperature control unit HT, the temperature of the electrostatic chuck ESC is adjusted, and the temperature of the wafer W mounted on the electrostatic chuck ESC is adjusted. . The temperature control unit HT may be embedded in the second plate 18b.

The temperature control unit HT includes a plurality of heating elements that emit heat and a plurality of temperature sensors that respectively detect temperatures around the plurality of heating elements. Each of the plurality of heating elements is provided for each of the plurality of areas ER of the main surface FW of the wafer W as shown in FIG. 3 when the wafer W is positioned and mounted on the electrostatic chuck ESC. It is done. The control unit Cnt is configured to set the heating element and the temperature sensor corresponding to each of the plurality of areas ER of the main surface FW of the wafer W when the wafer W is aligned and mounted on the electrostatic chuck ESC. Recognize in relation to The control unit Cnt can identify the region ER and the heating element and the temperature sensor corresponding to the region ER for each of the plurality of regions (for each of the plurality of regions ER) by, for example, numbers such as numbers and characters. The control unit Cnt detects the temperature of the one area ER by the temperature sensor provided at the location corresponding to the one area ER, and the temperature adjustment for the one area ER corresponds to the one area ER It is performed by the heating element provided at the location. Note that the temperature detected by one temperature sensor when wafer W is placed on electrostatic chuck ESC is the same as the temperature of region ER of the wafer W on the temperature sensor, and a diagram described later 4 (a), it is the same as the temperature of the region ER on the main surface FW of the wafer W, more specifically, the temperature of the mask MK and the to-be-etched layer EL in the region ER is there.

The plasma processing apparatus 10 includes an upper electrode 30. The upper electrode 30 is disposed to face the mounting table PD above the mounting table PD. The lower electrode LE and the upper electrode 30 are provided substantially in parallel with each other to constitute a parallel plate electrode. A processing space Sp for performing plasma processing on the wafer W is provided between the upper electrode 30 and the lower electrode LE.

The upper electrode 30 is supported on the top of the processing container 12 through the insulating shielding member 32. The insulating shielding member 32 is made of an insulating material, and may contain oxygen, for example, like quartz. The upper electrode 30 may include an electrode plate 34 and an electrode support 36. The electrode plate 34 faces the processing space Sp, and the electrode plate 34 is provided with a plurality of gas discharge holes 34 a. The electrode plate 34 contains silicon (hereinafter sometimes referred to as silicon) in one embodiment. In another embodiment, the electrode plate 34 may contain silicon oxide.

The electrode support 36 detachably supports the electrode plate 34, and may be made of a conductive material such as aluminum. The electrode support 36 may have a water cooling structure. Inside the electrode support 36, a gas diffusion chamber 36a is provided. A plurality of gas flow holes 36b communicating with the gas discharge holes 34a extend downward from the gas diffusion space 36a.

The plasma processing apparatus 10 includes a first high frequency power supply 62 and a second high frequency power supply 64. The first high frequency power source 62 is a power source that generates a first high frequency power for plasma generation, and generates a frequency of 27 to 100 MHz, and in one example, a high frequency power of 60 MHz. The first high frequency power supply 62 is provided with a pulse specification, and can be controlled at a frequency of 0.1 to 50 [kHz] and a duty of 5 to 100%. The first high frequency power supply 62 is connected to the upper electrode 30 via the matching unit 66. The matching unit 66 is a circuit for matching the output impedance of the first high frequency power supply 62 and the input impedance on the load side (lower electrode LE side). The first high frequency power supply 62 may be connected to the lower electrode LE via the matching unit 66.

The second high frequency power supply 64 is a power supply that generates a second high frequency power for drawing ions into the wafer W, that is, a high frequency bias power, and has a frequency in the range of 400 [kHz] to 40.68 [MHz], In one example, high frequency bias power of 13.56 MHz is generated. The second high frequency power supply 64 has a pulse specification, and can be controlled at a frequency of 0.1 to 50 [kHz] and a duty of 5 to 100%. The second high frequency power supply 64 is connected to the lower electrode LE via the matching unit 68. The matching unit 68 is a circuit for matching the output impedance of the second high frequency power supply 64 and the input impedance on the load side (lower electrode LE side).

The plasma processing apparatus 10 further includes a power supply 70. The power source 70 is connected to the upper electrode 30. The power supply 70 applies a voltage to the upper electrode 30 to draw positive ions present in the processing space Sp into the electrode plate 34. In one example, power supply 70 is a DC power supply that generates a negative DC voltage. When such a voltage is applied from the power supply 70 to the upper electrode 30, positive ions present in the processing space Sp collide with the electrode plate. Thereby, secondary electrons and / or silicon can be emitted from the electrode plate 34.

An exhaust plate 48 is provided on the bottom side of the processing container 12 and between the support portion 14 and the side wall of the processing container 12. The exhaust plate 48 can be configured, for example, by coating an aluminum material with a ceramic such as Y ₂ O ₃ . An exhaust port 12 e is provided below the exhaust plate 48 and in the processing container 12. An exhaust device 50 is connected to the exhaust port 12 e via an exhaust pipe 52. The exhaust device 50 has a vacuum pump such as a turbo molecular pump, and can reduce the pressure in the processing container 12 to a desired degree of vacuum. A loading / unloading port 12g of the wafer W is provided on a side wall of the processing container 12, and the loading / unloading port 12g can be opened and closed by a gate valve 54.

The gas source group 40 has a plurality of gas sources. The plurality of gas sources include a source of an aminosilane-based gas containing organic, a source of a fluorocarbon-based gas (C _x F _y gas (x, y is an integer of 1 to 10)), a gas having oxygen atoms (oxygen gas etc.) And sources of various gases, such as sources of inert gas. As the organic-containing aminosilane-based gas, a gas having a molecular structure with a relatively small number of amino groups can be used. For example, monoaminosilane (H ₃ —Si—R (R contains organic and is substituted) (Optionally amino group) may be used. The above-mentioned organic-containing aminosilane-based gas (a gas contained in the second gas G1 described later) can contain an aminosilane that can have 1 to 3 silicon atoms, or 1 to 3 amino groups Can contain an aminosilane having The aminosilane having 1 to 3 silicon atoms is a monosilane having 1 to 3 amino groups (monoaminosilane), a disilane having 1 to 3 amino groups, or a trisilane having 1 to 3 amino groups It can be. Furthermore, the above aminosilane can have an amino group which may be substituted. Furthermore, the above amino group may be substituted by any of methyl group, ethyl group, propyl group and butyl group. Furthermore, the above methyl, ethyl, propyl or butyl groups may be substituted by halogen. As a fluorocarbon-based gas (a gas contained in a first gas described later), any fluorocarbon-based gas such as CF ₄ gas, C ₄ F ₆ gas, or C ₄ F ₈ gas may be used. As the inert gas, any gas such as nitrogen gas, Ar gas, or He gas can be used.

The valve group 42 includes a plurality of valves, and the flow controller group 44 includes a plurality of flow controllers such as a mass flow controller. Each of the plurality of gas sources of the gas source group 40 is connected to the gas supply pipe 38 and the gas supply pipe 82 via the corresponding valve of the valve group 42 and the corresponding flow controller of the flow controller group 44. . Therefore, the plasma processing apparatus 10 can supply the gas from one or more selected gas sources among the plurality of gas sources of the gas source group 40 into the processing container 12 at the individually adjusted flow rate. It is.

In the plasma processing apparatus 10, as described later, since the organic-containing aminosilane-based gas is supplied, the plasma processing apparatus 10 includes a pipe for supplying the organic-containing aminosilane-based gas and other process gases (for example, oxygen gas). It has a postmix structure that separates it from the supply piping. Since the organic silane containing aminosilane is relatively reactive, if the supply of the organic silane containing the gas and the supply of the other process gas are carried out by the same pipe, the organic containing gas adsorbed in the pipe is contained. The components of the aminosilane-based gas may react with the components of other process gases, and reaction products resulting from this reaction may be deposited in the piping. The reaction products deposited in the pipe are difficult to remove by cleaning or the like, and may cause particles and cause abnormal discharge when the position of the pipe is close to the plasma region. Therefore, the supply of the organic-containing aminosilane gas and the supply of the other process gas need to be performed in separate pipes. Due to the post-mix structure of the plasma processing apparatus 10, the supply of the organic silane containing aminosilane gas and the supply of the other process gas are performed by separate pipes.

The post-mix structure of the plasma processing apparatus 10 includes at least two pipes (a gas supply pipe 38 and a gas supply pipe 82). A gas source group 40 is connected to each of the gas supply pipe 38 and the gas supply pipe 82 via a valve group 42 and a flow rate controller group 44.

The processing container 12 is provided with a gas inlet 36 c (first gas inlet). The gas inlet 36 c is provided above the wafer W disposed on the mounting table PD in the processing container 12. The gas inlet 36 c is connected to one end of the gas supply pipe 38. The other end of the gas supply pipe 38 is connected to the valve group 42. The gas inlet 36 c is provided in the electrode support 36. The gas introduction port 36c includes a first gas (a gas containing a fluorocarbon gas-based gas), a backflow prevention gas (a gas containing an inert gas) described later, and a third gas (described later) in the gas diffusion chamber 36a. A gas containing an oxygen atom) and a purge gas (a gas containing an inert gas and the like) described later are introduced. The gas supplied from the gas inlet 36 c to the processing space Sp via the gas diffusion space 36 a is supplied to the space area on the wafer W and between the wafer W and the upper electrode 30.

The processing container 12 is provided with a gas inlet 52 a (second gas inlet). The gas inlet 52 a is provided on the side of the wafer W disposed on the mounting table PD in the processing container 12. The gas inlet 52 a is connected to one end of the gas supply pipe 82. The other end of the gas supply pipe 82 is connected to the valve group 42. The gas inlet 52 a is provided on the side wall of the processing container 12. The gas inlet port 52a guides a second gas G1 (a gas containing an organic silane containing an aminosilane gas) and a backflow prevention gas (a gas containing an inert gas or the like) described later to the processing space Sp. The gas supplied from the gas inlet 52 a to the processing space Sp is supplied to the space area on the wafer W and between the wafer W and the upper electrode 30.

The gas supply pipe 38 connected to the gas inlet 36 c and the gas supply pipe 82 connected to the gas inlet 52 a do not intersect with each other. In other words, the supply path of the first gas and the third gas including the gas inlet 36 c and the gas supply pipe 38, and the supply path of the second gas G 1 including the gas inlet 52 a and the gas supply pipe 82 are: , Do not cross each other.

In the plasma processing apparatus 10, a deposition shield 46 is detachably provided along the inner wall of the processing container 12. The depot shield 46 is also provided on the outer periphery of the support portion 14. The deposition shield 46 prevents adhesion of the etching by-product (deposition) to the processing container 12 and can be configured by coating an aluminum material with a ceramic such as Y ₂ O ₃ . In addition to Y ₂ O ₃ , the deposition shield may be made of, for example, a material containing oxygen such as quartz.

The control unit Cnt is a computer including a processor, a storage unit, an input device, a display device, and the like, and controls each unit of the plasma processing apparatus 10 illustrated in FIG. The controller Cnt controls the valve group 42, the flow rate controller group 44, the exhaust device 50, the first high frequency power supply 62, the matching unit 66, the second high frequency power supply 64, the matching unit 68, the power supply 70 in the plasma processing apparatus 10. It is connected to the heater power supply HP, the chiller unit and the like.

The control unit Cnt operates in accordance with a computer program (a program based on an input recipe) for controlling each part of the plasma processing apparatus 10 in each process of the method MT, and sends out a control signal. Each part of the plasma processing apparatus 10 is controlled by a control signal from the control unit Cnt. Specifically, in the plasma processing apparatus 10 shown in FIG. 2, the control unit Cnt uses the control signal to select and flow the gas supplied from the gas source group 40, exhaust the exhaust device 50, and the first high frequency power. It is possible to control power supply from the power supply 62 and the second high frequency power supply 64, voltage application from the power supply 70, power supply of the heater power supply HP, the refrigerant flow rate from the chiller unit, the refrigerant temperature, and the like. In addition, each process of method MT which processes the to-be-processed object disclosed in this specification may be performed by operating each part of the plasma processing apparatus 10 by control by the control part Cnt. In the storage unit of the control unit Cnt, a computer program for executing the method MT and various data used for executing the method MT are readably stored.

Referring back to FIG. 1, the method MT will be described in detail. Hereinafter, an example in which the plasma processing apparatus 10 is used to perform the method MT will be described. In the following description, reference is made to FIG. 4, FIG. 5 and FIG. 4 includes (a), (b) and (c), and (a) of FIG. 4 is a cross-sectional view showing the state of the object to be processed before the process shown in FIG. FIG. 4 (b) is a cross-sectional view showing the state of the object to be processed after the execution of etching shown in FIG. 1, and FIG. 4 (c) is the object to be processed after execution of multiple sequences shown in FIG. It is sectional drawing which shows the state of. FIG. 5 is a view showing the state of supply of gas and supply of high frequency power during execution of each step of the method shown in FIG. 6 includes (a), (b), and (c), and (a) of FIG. 6 is a diagram schematically showing the state of the object before execution of the sequence shown in FIG. 1, for example. 6 (b) schematically shows the state of the object being processed during execution of the sequence shown in FIG. 1, and FIG. 6 (c) shows the state after execution of the sequence shown in FIG. It is a figure which shows the state of a to-be-processed object typically.

As shown in FIG. 1, the method MT includes a process ST1, a sequence SQ1, and a process ST3. Before execution of the process ST1 of the method MT, first, a wafer W which is an object to be processed is prepared. The wafer W to be prepared includes the layer to be etched EL and the mask MK, as shown in FIG. The mask MK is provided on the main surface ELa of the layer to be etched EL. An opening OP reaching the main surface ELa of the layer to be etched EL is formed in the mask MK. The opening OP may be an opening such as a groove, a hole or the like. The main surface ELa of the layer to be etched EL is partially exposed through the opening OP. The mask MK includes a side surface MKa and a surface MKb. The side surface MKa is included in the inner surface OPa of the opening OP. The surface MKb is included in the main surface FW of the wafer W.

The layer to be etched EL is a layer composed of a material that is selectively etched with respect to the mask MK, and for example, a hydrophilic insulating layer containing silicon is used. More specifically, the layer to be etched EL may include, for example, silicon oxide (SiO ₂ ). The layer to be etched EL may include other materials such as silicon nitride (Si ₃ N ₄ ) and polycrystalline silicon.

The mask MK is provided on the main surface ELa of the layer to be etched EL. The mask MK is a resist mask containing a resist material such as ArF, and is formed by patterning a resist layer by photolithography. The mask MK partially covers the main surface ELa of the layer to be etched EL. The openings OP define the pattern shape of the mask MK. The pattern shape of the mask MK is, for example, a line and space pattern. Note that the mask MK may have a pattern that provides a circular opening in plan view. Alternatively, the mask MK may have a pattern that provides an elliptical opening in plan view.

Before execution of step ST1, the wafer W shown in FIG. 4A described above is prepared, the wafer W is accommodated in the processing container 12 of the plasma processing apparatus 10, and is positioned on the mounting table PD and placed thereon. Be done. The control unit Cnt corresponds the temperature of each of the plurality of areas ER of the wafer W to each of the areas ER during the execution of the method MT shown in FIG. 1 (at least the execution of the step ST2a included in the method MT). A temperature sensor of the temperature control unit HT provided at a location detects the temperature of each of the regions ER by the heating element of the temperature control unit HT provided at a location corresponding to each of the regions ER. The temperature control performed by the control unit Cnt using the temperature control unit HT may make the temperature of the wafer W uniform in all of the plurality of regions ER.

In step ST1, the to-be-etched layer EL of the wafer W shown in FIG. 4A is etched. The step ST1 is a step of anisotropically etching the layer to be etched EL through the opening OP. In step ST1, a plasma of a first gas is generated in the processing space Sp of the processing container 12 of the plasma processing apparatus 10 in which the wafer W is accommodated. The process ST1 is performed by using a gas source selected from among the plurality of gas sources of the gas source group 40 and processing the first gas from the gas introduction port 36c through the gas supply pipe 38 as shown by the code FG1 in FIG. The backflow prevention gas is supplied into the processing space Sp of the processing container 12 from the gas introduction port 52a through the gas supply pipe 82 as shown by the code FG2 in FIG. The first gas may be appropriately selected according to the material constituting the layer to be etched EL. The first gas comprises carbon and fluorine atoms. For example, when the layer to be etched EL is a silicon oxide film, the processing gas may include a fluorocarbon-based gas. In order to prevent the backflow prevention gas from invading the gas supply pipe 82 through the gas introduction port 52a, the first gas and the plasma ions of the first gas supplied to the processing space Sp, etc. The processing space Sp is supplied to the processing space Sp. The backflow preventing gas may include, for example, an inert gas. Further, high frequency power is supplied from the first high frequency power supply 62 as indicated by reference numeral FG3 in FIG. In addition, as indicated by reference character FG4 in FIG. 5, high frequency bias power is supplied from the second high frequency power supply 64. Furthermore, by operating the exhaust device 50, the pressure of the space in the processing space Sp is set to a preset pressure. Thereby, a plasma is generated. The active species in the generated plasma is etched in the entire region of the main surface ELa of the layer to be etched EL, the region exposed from the mask MK through the opening OP. By step ST1, as shown in FIG. 4B, the pattern of the mask MK (the pattern defined by the opening OP) is transferred to the layer to be etched EL.

The layer to be etched EL is etched by the etching performed in the step ST1, and the inside of the opening OP reaches the inside of the layer to be etched EL. As shown in (b) of FIG. 4, in the etching performed in step ST1, the component contained in the first gas for the portion of the side surface MKa of the mask MK and the surface MKb of the mask MK in the opening OP. The reaction product containing H.sub.2 is deposited, and the deposition causes the deposition portion NC which is the reaction product to adhere to the opening OP. That is, necking occurs in which the opening OP is blocked by the deposition of the reaction product (deposition of the deposition portion NC). The plasma ions generated in step ST1 are incident on the wafer W perpendicularly (anisotropically) with respect to the main surface FW of the wafer W. However, when the deposition unit NC is attached, the plasma ions are incident on the deposition unit NC. By colliding, the traveling direction of plasma ions is bent and the anisotropy of plasma ions is lost. Therefore, the inner surface OPa of the opening OP (the side MKa of the mask MK among the inner sides of the opening OP, the side ELb of the etched layer EL of the inner sides of the opening OP, and the inner of the opening OP) The plasma ions collide with the bottom surface ELc in the layer to be etched EL, including the bottom surface ELc, and so on), and a bowing shape is formed on the surface OPa inside the opening OP.

In order to simultaneously perform the removal of the deposition part NC attached to the opening OP by the execution of the step ST1 and the compensation of the bowing shape formed on the surface OPa inside the opening OP by the execution of the step ST1, a sequence SQ1 following the step ST1 And process ST3 is performed over multiple times. The sequences SQ1 and ST3 are steps of forming the film BF on the surface OPa inside the opening OP after the execution of the step ST1 of etching the layer to be etched EL.

After step ST1, sequence SQ1 is executed. The sequence SQ1 includes a process T2a (first process), a process ST2b (second process), a process ST2c (third process), and a process ST2d (fourth process). The method MT is repeatedly performed on the sequence SQ1 multiple times. By the sequence SQ1 and the process ST3, the sequence SQ1 is repeatedly executed a plurality of times, and the film BF is formed on the surface OPa inside the opening OP. A series of processes from the start of the sequence SQ1 to the process ST3 described later: YES simultaneously remove the deposition portion NC attached to the opening OP by the process ST1 and compensate the bowing shape formed on the side surface MKa and the side surface ELb simultaneously. This is a step of repairing the shape in the opening OP, more specifically, the shape of the inner surface OPa of the opening OP to a desired shape. The compensation of the bowing shape formed on the side surface MKa and the side surface ELb is performed by forming the film BF on the portion of the bowing shape formed on the surface OPa inside the opening OP. The film BF is a silicon oxide film containing silicon oxide (SiO ₂ ).

The process ST2a supplies the second gas G1 from the gas inlet 52a to the processing space Sp of the processing container 12 through the gas supply pipe 82 as shown by the code FG2 in FIG. As shown, the backflow prevention gas is supplied into the processing space Sp of the processing container 12 from the gas inlet 36 c through the gas supply pipe 38. The second gas G1 contains an organic-containing aminosilane-based gas. The process ST 2 a supplies the second gas G 1 into the processing space Sp of the processing container 12 from a selected gas source among the plurality of gas sources of the gas source group 40. As the second gas G1, for example, monoaminosilane (H ₃ —Si—R (R is an amino group)) can be used as an organic-containing aminosilane-based gas. In the process ST2a, plasma of the second gas G1 is not generated as indicated by reference numerals FG3 and FG4 in FIG. The molecule of the second gas G1 (monoaminosilane) adheres to the inner surface OPa of the opening OP (specifically, a portion of the surface OPa to which the deposition portion NC is not attached) by chemisorption based on a chemical bond No plasma is used in step ST2a. Note that the second gas G1 can be attached to the surface OPa (specifically, a portion of the surface OPa to which the deposition portion NC is not attached) by chemical bonding and contains silicon, It may be a gas other than monoaminosilane. The backflow prevention gas is supplied from the gas inlet 36c to the processing space Sp in order to prevent the second gas G1 supplied to the processing space Sp from entering the gas supply pipe 38 via the gas inlet 36c. Ru. The backflow preventing gas may include, for example, an inert gas.

The reason why a monoaminosilane-based gas is selected as the second gas G1 is that chemical adsorption is relatively easily performed by the monoaminosilane having a relatively high electronegativity and a molecular structure having polarity. It is due to getting. As shown in (a) of FIG. 6 and (b) of FIG. 6, the molecules of the second gas G1 adhere to the surface OPa inside the opening OP (specifically, the deposition portion NC adheres to the surface OPa). Layer Ly1 formed by adhering to the surface OPa shown in (a) to (c) of FIG. 6 is a single molecule because the adhesion is chemisorption It will be close to a layer (monolayer). The smaller the amino group (R) of the monoaminosilane, the smaller the molecular structure of the molecule adsorbed on the surface OPa inside the opening OP, so that the steric hindrance due to the size of the molecule is reduced, and thus the second The molecules of the gas G1 can be uniformly adsorbed on the inner surface OPa of the opening OP, and the layer Ly1 can be formed with a uniform film thickness on the inner surface OPa of the opening OP. For example, the reaction precursor H ₃ -Si-O is reacted by reacting monoaminosilane (H ₃ -Si-R) contained in the second gas G1 with the hydrophilic OH group of the surface OPa inside the opening OP. Is formed, and thus, it is conceivable that the layer Ly1, which is a monolayer of H ₃ —Si—O, is formed. Therefore, the layer Ly1 of the reaction precursor can be formed conformally to the surface OPa inside the opening OP. In addition, since the deposition part NC attached to the opening OP contains a hydrophobic compound containing a carbon atom and a fluorine atom, the layer Ly1 is not formed in the deposition part NC, but as described later, a plurality of times of the sequence SQ1 is performed. Depending on the implementation, the deposition portion NC may be physically removed, and the layer Ly1 may be formed on the surface OPa inside the opening OP exposed after the removal of the deposition portion NC.

The aminosilane-based gas contained in the second gas G1 may contain, in addition to monoaminosilane, an aminosilane having 1 to 3 silicon atoms, and an aminosilane-based gas contained in the second gas G1. The gas may contain an aminosilane having 1 to 3 amino groups.

In step ST2a, the etching target layer EL is etched through the opening OP while adjusting the temperature of the wafer W to be uniform over the plurality of areas ER of the wafer W. That is, during the process ST2a, the control unit Cnt controls the temperature control unit HT so that the temperature of the wafer W (particularly, the mask MK and the layer to be etched EL of the wafer W) becomes uniform in all of the plurality of areas ER. The temperature control on the wafer W is continuously performed using this. The degree of chemical attachment (chemisorption) of molecules of the second gas G1 (for example, monoaminosilane) to the hydrophilic surface OPa inside the opening OP depends on the temperature of the surface OPa. Specifically, when a molecule of the second gas G1 (eg, monoaminosilane) is chemisorbed on the hydrophilic surface OPa inside the opening OP, the Arrhenius equation showing the correlation between the reaction rate of the chemical reaction and the temperature As shown in (Arrhenius equation), the higher the temperature of the surface OPa, the higher the reaction rate of chemisorption, and thus the greater the number of molecules of the second gas G1 chemisorbed on the surface OPa. Therefore, as the temperature of the surface OPa is higher, the film thickness of the layer Ly2 formed on the surface OPa is increased, and the film thickness of the film BF formed on the surface OPa is also increased by execution of multiple times of the sequence SQ1. For this reason, in order to form the film BF having the same film thickness in all the plurality of regions ER of the wafer W, the wafer W (particularly, the mask MK and the etching target layer EL of the wafer W) at least during the process ST2a. It is necessary to continuously adjust the temperature of the wafer W (in particular, the mask MK and the layer to be etched EL of the wafer W) so that the temperature of all the regions ER is uniform.

In a process ST2b subsequent to the process ST2a, the processing space Sp of the processing container 12 is purged. Specifically, the second gas G1 supplied in the process ST2a is exhausted. For example, the process ST2b may supply an inert gas such as nitrogen gas as a purge gas into the processing space Sp of the processing container 12 through the gas supply pipe 38 and the gas inlet 36c. That is, the purge in the step ST2b may be either a gas purge in which an inert gas is flowed into the processing space Sp or a purge by evacuation. In the step ST2b, molecules excessively attached to the surface OPa inside the opening OP can also be removed. By the above, the layer Ly1 of the reaction precursor becomes an extremely thin monolayer.

A process ST2c subsequent to the process ST2b generates a plasma P1 of a third gas in the processing container 12. Step ST2c is a third gas containing oxygen atoms from a gas inlet 36c through a gas supply pipe 38 from a selected gas source among the plurality of gas sources of the gas source group 40 as indicated by a symbol FG1 in FIG. Is supplied into the processing space Sp of the processing container 12 and, as shown by the code FG2 in FIG. 5, the backflow preventing gas is supplied into the processing space Sp of the processing container 12 from the gas introduction port 52a via the gas supply pipe 82. . The third gas is a gas containing an oxygen atom, and may be, for example, an oxygen gas. The backflow prevention gas is supplied from the gas inlet 52 a to the processing space Sp in order to prevent the third gas supplied to the processing space Sp from intruding into the gas supply pipe 82 through the gas inlet 52 a. . The backflow preventing gas may include, for example, an inert gas. Then, high frequency power is supplied from the first high frequency power supply 62 as indicated by reference numeral FG3 in FIG. In this case, the bias power of the second high frequency power supply 64 can also be applied as indicated by the symbol FG4 in FIG. In addition, plasma can be generated using only the second high frequency power supply 64 without using the first high frequency power supply 62. By operating the exhaust system 50, the pressure of the space in the processing space Sp is set to a preset pressure.

As described above, the molecules attached to the surface OPa inside the opening OP by the execution of the step ST2a (the molecules that constitute the monolayer of the layer Ly1) include a bond of silicon and hydrogen. The bonding energy of silicon and hydrogen is lower than the bonding energy of silicon and oxygen. Therefore, as shown in (b) of FIG. 6, when the plasma P1 of the third gas containing oxygen atoms is generated, active species of oxygen, for example, oxygen radicals are generated, and a monolayer of the layer Ly1 is formed. hydrogen molecules constituting the is replaced with oxygen, as shown in (c) of FIG. 6, the layer Ly2 a silicon oxide film (SiO ₂ film) is formed as a monomolecular layer.

The process ST2d following the process ST2c purges the processing space Sp of the processing container 12. Specifically, the third gas supplied in step ST2c is exhausted. For example, in the process ST2d, an inert gas such as nitrogen gas may be supplied as the purge gas to the processing space Sp via the gas supply pipe 38 and the gas inlet 36c. That is, the purge in the step ST2d may be either a gas purge in which an inert gas is flowed into the processing space Sp or a purge by evacuation.

In the sequence SQ1 described above, the purge is performed in the process ST2b, and in the process ST2c following the process ST2b, the hydrogen of the molecule forming the layer Ly1 is replaced with oxygen. Therefore, as in the ALD (Atomic Layer Deposition) method, the execution of one sequence SQ1 causes the layer Ly2 of the silicon oxide film to be a part of the surface OPa inside the opening OP to which the deposition portion NC is not attached (Bowing It can be formed conformally with a thin and uniform film thickness). As used herein, ALD refers to atomic layer deposition that deposits one atomic layer at a time.

Since the deposition part NC contains a hydrophobic compound containing a carbon atom and a fluorine atom, the layer Ly1 is not formed in the deposition part NC. By execution of one sequence SQ1, one or more atomic layers of the deposition part NC are removed from the surface of the deposition part NC.

In step ST3 subsequent to sequence SQ1, it is determined whether or not the execution of sequence SQ1 ends. Specifically, in step ST3, it is determined whether the number of executions of the sequence SQ1 has reached a preset number. The determination of the number of times of execution of the sequence SQ1 is to determine the film thickness of the film BF shown in FIG. 4C. More specifically, the deposition portion NC of the surface OPa inside the opening OP is a product of the film thickness of the silicon oxide film (layer Ly2) formed by execution of one sequence SQ1 and the number of executions of the sequence SQ1. The thickness of the film BF formed on the portion (including the portion having a bowing shape) not attached is substantially determined. Therefore, the number of times of execution of sequence SQ1 is set according to the desired thickness of film BF formed on a portion (including a portion having a bowing shape) to which deposition portion NC is not attached among surface OPa inside opening OP. Ru.

In the portion of the surface OPa inside the opening OP to which the deposition portion NC is attached, the deposition portion NC is removed by execution of the first sequence after the step ST1 or multiple times of the sequence SQ1 including the first sequence, and the side surface MKa and side surfaces The film BF is formed only by the execution of the sequence SQ1 after the ELb is exposed. Execution of multiple sequences SQ1 including the first step after step ST1 or the first step removes the deposited portion NC having a hydrophobic surface (including a compound containing a carbon atom and a fluorine atom) and a hydrophilic surface (OH group) Is exposed, the monoaminosilane (H ₃ -Si-R) contained in the second gas G1 by execution of step ST2a of the sequence SQ1 after removal of the deposition part NC when the side surface MKa and the side surface ELb are exposed. Is reacted with the hydrophilic OH group of the surface OPa inside the opening OP to form a reaction precursor H ₃ -Si-O, and thus, a layer Ly 1 which is a monolayer of H ₃ -Si-O. Is formed. Thus, the number of executions of the sequence SQ1 until the film BF is formed on the portion of the surface OPa inside the opening OP to which the deposition portion NC is attached is smaller than the number of executions of the sequence SQ1. The film thickness of the film BF formed on the portion of the inner surface OPa to which the deposition portion NC is attached is the portion of the surface OPa on the inner side of the opening OP to which the deposition portion NC is not attached And the film thickness of the film BF formed on

If it is determined in step ST3 that the number of executions of the sequence SQ1 has not reached the preset number (step ST3: NO), the execution of the sequence SQ1 is repeated again. On the other hand, when it is determined in step ST3 that the number of times of execution of the sequence SQ1 has reached the preset number (step ST3: YES), the execution of the sequence SQ1 is ended. By repeating the number of times of execution of sequence SQ1 the preset number of times (step ST3: YES), as shown in (c) of FIG. 4, the deposition portion NC is removed, and the surface OPa inside the opening OP. A film BF of silicon oxide film is formed on the

The film BF formed on the portion of the inner surface OPa of the opening OP to which the deposition portion NC is not attached is formed mainly at the portion of the bowing shape (the recess in the opening OP) on the inner surface OPa of the opening OP Be done. The film thickness of the film BF formed on a portion (including a portion having a bowing shape) to which the deposition portion NC is not attached among the surface OPa inside the opening OP is the deposition portion NC among the surface OPa inside the opening OP. It is thicker than the film thickness of the film BF formed on the adhered portion. Accordingly, by repeating the execution of sequence SQ1 until it is determined in step ST3 that the number of executions of sequence SQ1 has reached the preset number, the bowing shape is compensated by the film BF and attached to the opening OP. Since the deposit portion NC is removed, the flatness of the surface OPa inside the opening OP can be sufficiently restored by the method MT.

The method MT includes a sequence SQ2 and a process ST4. The sequence SQ2 includes the above-described process ST1, the sequence SQ1, and the process ST3. The method MT executes the sequence SQ2 one or more times. Step ST4 following the sequence SQ2 (step ST3: following YES) determines whether or not the execution of the sequence SQ2 is ended. Specifically, the process ST4 determines whether or not the number of times of execution of the sequence SQ2 has reached a preset number of times. If it is determined in step ST4 that the number of executions of the sequence SQ2 has not reached the preset number (step ST4: NO), the execution of the sequence SQ2 is repeated again. On the other hand, if it is determined in step ST4 that the number of executions of the sequence SQ2 has reached the preset number (step ST4: YES), the execution of the sequence SQ2 is ended. By repeating the sequence SQ2 in this manner, the depth inside the opening OP can be adjusted to a desired depth while maintaining the flatness and shape of the surface inside the opening OP.

A portion of the surface OPa inside the opening OP to which the deposition portion NC is not attached while the deposition portion NC which is a reaction product due to the first gas adheres to the opening OP by the etching performed in the step ST1 A bowing shape (dent) may be formed in the exposed portion of the layer to be etched EL. According to the method MT according to the embodiment described above, the deposition portion NC attached to the opening OP is removed and the bowing shape is formed by the sequence SQ1 and the step ST3 executed after the execution of the step ST1. The bowing shape can be relaxed by forming the film BF in the portion.

Further, in step ST2a using the second gas, a chemical reaction is used without generating plasma, so that the thickness of the film BF formed by the sequence SQ1 including the step ST2a and the step ST3 is the film BF. Increases as the temperature of the wafer W (particularly, the layer to be etched EL) to be formed is increased. Therefore, according to the method MT, the thickness of the film BF formed in the sequence SQ1 and the process ST3 can be uniform over the plurality of regions ER of the wafer W.

In addition, a gas inlet 52a for introducing a second gas containing a relatively reactive organic-containing aminosilane-based gas used in step ST2a into the processing container 12, and carbon atoms and fluorine atoms used in step ST1. And the gas introduction port 36c for introducing the third gas containing oxygen atoms used in the process ST2c into the processing container and different from each other, and the gas supply pipe connected to the gas introduction port 36c is different from each other. Since the gas supply pipe 82 connected to the gas inlet 52a does not intersect with each other, the second gas containing the relatively reactive organic-containing aminosilane gas, the first gas, and the third gas It is possible to reduce reaction products that can be generated in the gas supply pipe (the gas inlet 36c and the gas inlet 52a) due to the gas. In addition, by using the backflow prevention gas, the first gas, the second gas, and the third gas are not flowing to the gas supply pipe (the gas inlet 36c or the gas inlet 52a) in a state where none of them is flowing. Backflow of any of the gas, the second gas, and the third gas can be avoided.

Further, the etching of the layer to be etched EL which is a hydrophilic insulating layer containing silicon can be performed in step ST1 using the first gas containing a fluorocarbon gas in the step ST1, and the second gas containing monoaminosilane is used to etch the silicon Formation of a reaction precursor can be performed in step ST2a.

As described above, according to the first embodiment, the bowing shape of the side surface of the recess caused by the etching can be relaxed.

Second Embodiment
Hereinafter, description will be made with reference to FIGS. 7 to 11. FIG. 7 is a flow chart illustrating a method MT of processing a wafer W according to an embodiment. The method MT includes a process ST1a and a process ST5, and is sequentially performed. The method MT may include ST1b after ST1a. In the second embodiment, the surface of the wafer W includes the surface SFa of the first area La of the wafer W and the surface SFb of the second area Lb of the wafer W. In one embodiment, the first film M1 is formed on the surface SFa of the first region La of the wafer W. A film is formed by ALD on the surface SFb of the second region Lb.

The control unit Cnt of the plasma processing apparatus 10 controls each part of the plasma processing apparatus 10 to perform the method MT.

FIGS. 8A and 8B are cross-sectional views showing the state of the wafer W after execution of each step of the method MT shown in FIG. 7. TM1 shown in (a) of FIG. 8 shows the state of the wafer at the timing of starting the process ST5. TM2 shown in (b) of FIG. 8 indicates the timing at which the process ST5 ends (in particular, the timing at which the removal of the first film M1 ends) ((a) in FIG. 9, (b) in FIG. Also in 11).

FIGS. 9A and 9B schematically show the removal of the first film M1 and the formation of the second film M2 by the method MT shown in FIG. FIG. 9A schematically shows the removal of the first film M1 and the formation of the second film M2 on the first region La. (B) of FIG. 9 schematically shows the formation of the second film M2 on the second region Lb. FIG. 10 shows how the film thickness of the first film M1 changes and the film thickness of the second film M2 changes according to the method MT shown in FIG. FIG. 11 shows another aspect of the change in film thickness by the method MT. The vertical axis in FIG. 10 indicates the film thickness of the first film M1. The vertical axis in FIG. 11 indicates the film thickness of the second film M2. Each horizontal axis of each of FIGS. 10 and 11 indicates the time from the start of the process.

The method MT shown in FIG. 7 will be described. The step ST1a is a step of selectively forming the first film M1 (FIG. 8A) on the wafer W. Specifically, in step ST1a, as shown in FIG. 8A, the first film M1 is formed on the surface SFa of the first area La of the wafer W, and the surface SFb of the second area Lb of the wafer W (Corresponding to the case shown in FIG. 10) or as a thinner film than the first film M1 formed on the surface SFa (corresponding to the case shown in FIG. 11). The process ST1a includes a process of preparing in advance a wafer W having a first region La made of a first material and a second region Lb made of a second material different from the first material. The first material and the second material will be described later.

In step ST1a, the first film M1 is formed using a fourth gas. The first film M1 can be formed by plasma enhanced chemical vapor deposition (PECVD), thermal CVD, or the like using a fourth gas. Another example includes the case where the first film M1 is formed by etching using the active species of the fourth gas. When the first material of the first region La contains, for example, any of silicon, organic substance or metal, and the second material of the second region Lb contains, for example, silicon and oxygen, the fourth gas is a fluorocarbon gas. You may When the first material of the first region La contains any of silicon, organic substance or metal and the second material of the second region Lb contains, for example, silicon and nitrogen, the fourth gas is fluorohydrocarbon gas May be there. Thus, the fourth gas is a gas having a depositability.

For example, when the second region Lb is SiO ₂ , the first film M1 is formed on the first region La by performing plasma etching using a gas such as C ₄ F ₆ or the like. On the other hand, for example, when the second region Lb is SiN, the first film M1 is formed on the first region La by performing plasma etching using a gas such as CH ₃ F.

Hereinafter, an example of forming the first film M1 by plasma etching will be described. According to this example, it is possible to further increase the difference in film thickness between the first film M1 formed on the first region La and the first film M1 that can be formed on the second region Lb. Process ST1a includes a fifth process and a sixth process. The fifth and sixth steps are performed in the plasma processing apparatus 10. In the process ST1a, the second region Lb is etched by plasma of a fourth gas in the fifth and sixth steps to form a first film M1 on the first region La.

First, plasma of a fourth gas is generated in the processing container 12 in which the wafer W is stored, and a film is deposited on the surface SFa of the first region La and the surface SFb of the second region Lb (fifth step) . The fifth step includes supplying a fourth gas into the processing vessel 12 and adjusting the pressure. Next, the first high frequency power supply 62 is operated to apply high frequency power to generate plasma of a fourth gas. In the fifth step, high-frequency power for drawing ions into the wafer W is not applied, or power for which etching does not occur is applied. Thus, a film is formed on the surface SFa of the first region La and the surface SFb of the second region Lb.

Then, the sixth step removes the second region Lb. In the sixth step, an inert gas is supplied into the processing container 12. The first high frequency power supply 62 is operated to apply high frequency power to generate plasma of inert gas. In the sixth step, the second high frequency power supply 64 may be operated to apply high frequency power. As a result, ions of the inert gas are drawn into the film deposited in the fifth step, and the deposited film reacts with part of the second region Lb, and part of the second region Lb is removed. In this etching, one atomic layer to ten atomic layers of the second region Lb are etched per cycle including the fifth step and the sixth step (referred to as pseudo ALE). On the other hand, since the reaction between the deposited film and the first region La does not easily form a highly volatile reaction product, the first region La is difficult to remove as compared to the second region Lb. Therefore, the first film M1 is formed in the first region La. The fifth and sixth steps are repeated until the etching amount of the second region Lb becomes a predetermined amount. After etching, no film or little film remains on the second region Lb. The present etching method improves the selectivity of the deposition amount of the first film M1. Here, the pseudo ALE is shown as an example of forming the first film by etching, but the second region Lb may be etched by another method to form the first film M1 on the first region La.

In one embodiment, the first region La has a first material containing any of silicon, organic matter, and metal. Specifically, the first material of the first region La is, for example, one or more of Si, SiGe, Ge, SiN, SiC, an organic film, a metal (W, Ti, etc.), SiON, SiOC A combination of The second region Lb may include a second material different from the first material constituting the first region La, and may contain silicon and oxygen. Specifically, the second region Lb has a second material containing SiO ₂ , SiON, SiOC or the like. The fourth gas may be a fluorocarbon gas such as C ₄ F ₆ or C ₄ F ₈ . The fourth gas may further comprise an inert gas. The inert gas used in the sixth step contains a noble gas such as argon.

In addition, in another embodiment, the first region La may contain any of silicon, an organic substance, and a metal, and the second region Lb may contain silicon and nitrogen. Specifically, the first region La may contain, for example, any of Si, SiO ₂ , SiC, an organic film, a metal (W, Ti, etc.), SiON, SiOC, etc., and the second region Lb is Any of SiN, SiON, etc. may be contained. In this embodiment, the fourth gas may be a fluorohydrocarbon-based gas. The fourth gas may further contain an inert gas. The inert gas used in the sixth step may contain a noble gas such as argon.

Refer again to FIG. The step ST5 is a step of forming the second film M2 by ALD on the second region Lb while removing the first film M1. Thus, in the process ST5, the second film M2 (FIG. 8B) is selectively formed on the surface of the wafer W by the ALD method. Step ST5 includes plasma processing, and repetition of the plasma processing removes the first film M1 on the first region La.

In the process ST5 of forming the second film M2, the total execution time of the process ST2c can be adjusted in accordance with a preset target value of the film thickness of the second film M2.

The process ST5 includes a sequence SQ1 and a process ST3. The sequence SQ1 includes a process ST2a, a process ST2b, a process ST2c, and a process ST2d. The sequence SQ1 may selectively include a process ST2e after the process ST2d. Step ST2e is a step of generating plasma of an inert gas. Thereby, the process ST2e densifies the second film M2 formed through the process ST2a, the process ST2b, the process ST2c, and the process ST2d. Also, the film thickness of the first film M1 may be adjusted by the process ST2e. The execution time of each of process ST2c and process ST2e may be adjusted.

The process ST1a and the process ST5 can be performed using the same plasma processing apparatus 10 continuously without breaking the vacuum. In another embodiment, steps ST1a and ST5 may be performed using different plasma processing apparatuses. When the process ST1a and the process ST5 are performed using different plasma processing apparatuses, in the process ST1a, the first film M1 is selectively formed using one plasma processing apparatus. Then, in step ST5, the wafer W on which the first film M1 is selectively provided is selectively exposed on the exposed surface of the wafer W by the ALD method using the plasma processing apparatus 10 different from the one plasma processing apparatus. The second film M2 is formed. While the sequence SQ1 is repeated to form the second film M2, the first film M1 on the first region La is removed. Specifically, the plasma of the reformed gas in the process ST2c or the plasma of the inert gas in the selectively performed process ST2e removes the first film M1 on the first region La. The amount of removal of the first film can be controlled by adjusting the value of the first or second high frequency power in the process ST2c during the process ST2.

The second gas G1 (precursor gas) used in the step ST2a is a gas that adsorbs to the area of the wafer W where the first film M1 is not formed and forms the adsorption layer (the layer Ly1 shown in FIG. 6) The first film M1 inhibits the adsorption of the second gas). The second gas G1 may be an aminosilane gas, a gas containing silicon, a gas containing titanium, a gas containing hafnium, a gas containing tantalum, a gas containing zirconium, and a gas containing organic matter . The third gas used in the step ST2c is a gas for reforming the adsorption layer, for example, a gas containing oxygen, a gas containing nitrogen, and a gas containing hydrogen.

Specifically, the third gas, _{O 2} gas, CO ₂ gas, NO gas, SO ₂ gas, _{N 2} gas, _{H 2} gas, NH ₃ gas or the like can be used. Although ozone gas (O ₃ gas) may be used as the _third gas, plasma may not be generated in the process ST 2 c.

(A) of FIG. 8 and (b) to 11 of FIG. 8 show the process executed in step ST5. As shown in FIG. 8A and FIG. 10, in the process ST1a, the first film M1 is selectively formed on the surface SFa of the first region La. The wafer W has a plurality of first regions La. The first film M1 is selectively formed in the plurality of first regions. In one embodiment, these first films M1 may have different film thicknesses in the plurality of first regions.

A line segment LP1 and a line segment LP2 shown in FIG. 10 indicate a change in film thickness of the first film M1 formed on the surface SFa of the first region La. Line segment LP3 shown in FIG. 10 shows a change in film thickness of the second film M2 formed on the surface SFb of the second region Lb. The line segment LP4 illustrated in FIG. 10 is formed on the surface SFa when the step ST5 of forming the second film M2 is continuously performed after the first film M1 is removed from the surface SFa of the first region La. Shows the change in the film thickness of the second film M2.

As shown in FIG. 8A and FIG. 10, the first film M1 is not deposited on the surface SFb of the second region Lb by the step 1a, or the surface as shown in FIG. 8A and FIG. A first film M1 thinner than the first film M1 formed on SFa may be formed.

A line segment LP1a and a line segment LP2a illustrated in FIG. 11 indicate a change in the film thickness of the first film M1 formed on the surface SFb when the first film M1 is formed on the surface SFb of the second region Lb.

As shown in FIG. 9A, FIG. 9B, FIG. 10, and FIG. 11, when the step ST5 is started at timing TM1, the repetition of the step ST5 removes the first film M1 stepwise. (The line segment LP2 in FIG. 10, the line segment LP2 in FIG. 11, and the line segment LP2 a). On the other hand, in the repetition of step 5, the surface SFb of the second region Lb where the first film M1 is not formed, or the surface SFb of the second region Lb where the first film M1 is removed Are formed one by one (line LP3 in FIG. 10 and FIG. 11).

In one embodiment, ST5 may be continuously performed from timing TM1 to timing TM2 at which all of the first film M1 of the surface SFa of the first region La is removed. The case where process ST5 is repeatedly performed 3 times is illustrated by (a) of FIG. 9, and (b) of FIG. That is, FIGS. 9A and 9B illustrate the case where the first film M1 on the first region La is completely removed by repeatedly performing the process ST5 three times. .

When step ST5 is first performed at timing TM1, the surface SFb of the second region Lb is exposed, but the surface SFa of the first region La is covered and not exposed by the first film M1. By performing step ST5 first at timing TM1, a part of the first film M1 covering the first region La is removed. A second film M2 of one atomic layer is formed on the exposed second region Lb.

Next, by the execution of the second step ST5, a part of the first film M1 on the first region La is further removed, and another atomic layer is formed on the second film M2 on the second region Lb. Thus, the second film M2 is a film of two atomic layers. Next, by the execution of the third process ST5, all the first film M1 on the first region La is removed, and one more atomic layer is formed on the second film M2 on the second region Lb. The film M2 is a film of three atomic layers. As described above, at the timing TM2 at which the process ST5 is repeated three times, all the first film M1 on the first region La is removed to expose the surface SFa of the first region La, and the second region Lb is exposed. A second film M2 of three atomic layers is formed.

In step ST5, as shown in FIGS. 9A, 9B, 10, and 11, timing TM2 in which all the first film M1 on the surface SFa of the first region La is removed from timing TM1. However, the present invention is not limited thereto. In another embodiment, the process may be continued until the film thickness of the first film M1 set in advance or the film thickness of the second film M2 set in advance is reached. It may be performed. For example, the process ST5 can be continued even after the timing TM2 at which all the first film M1 of the surface SFa is removed. In this case, as shown in (a) and (b) of FIG. 9 and after timing T2 in FIG. 9 and in line segment LP4 in FIG. 10 and FIG. The second film M2 is sequentially formed one atomic layer at a time on the (exposed) surface SFa of La, and the second film M2 is increased by one atomic layer even on the second region Lb.

FIGS. 9A and 9B illustrate the case where the process ST5 is repeated three times (cycles) after timing TM2. Step ST5 is repeated three times after timing TM2 to form a second film M2 of three atomic layers on the first region La, and form a second film M2 of six atomic layers on the second region Lb. Be done.

In one embodiment, a first film having a different film thickness for each region is formed on the wafer W, and a second film M2 having a different thickness according to the region is formed by repeating the ALD cycle. That is, the second film M2 may be formed to have a plurality of film thicknesses in accordance with the plurality of film thicknesses of the first film M1.

Several specific examples of the process conditions which can be used in process ST1a, process ST2a, and process ST2c are shown in the following Examples 1 to 3.

Example 1
-Material of the first region La: SiN
· Material of second region Lb: SiO ₂
<Step ST1a>
-Pressure in the processing space Sp: 20 [mTorr]
Power from the first high frequency power supply 62: 500 [W]
・ Power from the second high frequency power supply 64: 0 [W]
First gas flow rate: C ₄ F ₆ gas (15 sccm) / Ar gas (350 sccm) / O ₂ gas (20 sccm)
・ Wafer W temperature: 200 ° C.
Execution time: 10 seconds
The first film M1 formed in the first embodiment is a fluorocarbon film.
<Step ST2a>
· Pressure in the processing space Sp: 100 mTorr
・ Power by the first high frequency power supply 62: 0 [W]
・ Power from the second high frequency power supply 64: 0 [W]
First gas flow rate: aminosilane-based gas (50 [sccm])
・ Wafer W temperature: 80 ° C.
Execution time: 15 seconds
<Step ST2c>
Pressure in the processing space Sp: 200 mTorr
· Power from the first high frequency power supply 62: 500 [W] (60 [MHz])
Power from the second high frequency power supply 64: 300 [W] (10 [kHz])
First gas flow rate: CO ₂ gas (300 [sccm])
Execution time: 5 seconds

(Example 2)
-Material of the first region La: SiN
· Material of second region Lb: SiO ₂
<Step ST1a>
An etching process is performed using the fifth and sixth steps described above.
The number of repetitions of the fifth and sixth steps: twice The first film M1 formed in Example 2 is a fluorocarbon film.
<Fifth step>
-Pressure in the processing space Sp: 30 [mTorr]
-Power from the first high frequency power supply 62: 100 [W]
・ Power from the second high frequency power supply 64: 0 [W]
-Voltage by the DC power supply 70: -300 [V]
Fourth gas flow rate: C ₄ F ₆ gas (16 [sccm]) / Ar gas (1000 [sccm]) / O ₂ gas (10 [sccm])
Execution time: 3 seconds
<Step 7>
-Pressure in the processing space Sp: 30 [mTorr]
Power from the first high frequency power supply 62: 500 [W]
・ Power from the second high frequency power supply 64: 0 [W]
-Voltage by the DC power supply 70: -300 [V]
Fourth gas flow rate: C ₄ F ₆ gas (0 [sccm]) / Ar gas (1000 [sccm]) / O ₂ gas (0 [sccm])
Execution time: 5 seconds
<Step ST2a>
· Pressure in the processing space Sp: 100 mTorr
・ Power by the first high frequency power supply 62: 0 [W]
・ Power from the second high frequency power supply 64: 0 [W]
First gas flow rate: aminosilane-based gas (50 [sccm])
・ Wafer W temperature: 80 ° C.
Execution time: 15 seconds
<Step ST2c>
Pressure in the processing space Sp: 200 mTorr
Power by the first high frequency power supply 62 (frequency: 60 [MHz]): 500 [W]
Power by the second high frequency power supply 64 (frequency: 10 [kHz]): 300 [W]
First gas flow rate: CO ₂ gas (300 [sccm])
Execution time: 5 seconds

(Example 3)
-Material of the first region La: SiN
· Material of second region Lb: SiO ₂
<Step ST1a>
The etching process using the above-described fifth and sixth steps is performed.
The number of repetitions of the fifth to eighth steps: twice The first film M1 formed in the third embodiment is a fluorocarbon film.
<Fifth step>
-Pressure in the processing space Sp: 30 [mTorr]
-Power from the first high frequency power supply 62: 100 [W]
・ Power from the second high frequency power supply 64: 0 [W]
-Voltage by the DC power supply 70: -300 [V] (the condition can be omitted)
Fourth gas: C ₄ F ₆ gas (16 [sccm]) / Ar gas (1000 [sccm]) / O ₂ gas (10 [sccm])
Execution time: 3 seconds
<Step 7>
-Pressure in the processing space Sp: 30 [mTorr]
Power from the first high frequency power supply 62: 500 [W]
・ Power from the second high frequency power supply 64: 0 [W]
-Voltage by the DC power supply 70: -300 [V]
Fourth gas: C ₄ F ₆ gas (0 [sccm]) / Ar gas (1000 [sccm]) / O ₂ gas (0 [sccm])
Execution time: 5 seconds
<Step ST2a>
· Pressure in the processing space Sp: 100 mTorr
・ Power by the first high frequency power supply 62: 0 [W]
・ Power from the second high frequency power supply 64: 0 [W]
First gas: aminosilane-based gas (50 [sccm])
・ Wafer W temperature: 80 ° C.
Execution time: 15 seconds
<Step ST2c>
Pressure in the processing space Sp: 200 mTorr
Power by the first high frequency power supply 62 (frequency 60 [MHz]): 500 [W]
Power by the second high frequency power supply 64 (frequency 10 [kHz]): 300 [W]
First gas: CO ₂ gas (300 [sccm])
・ Execution time: 2 [seconds]

Example 2 and Example 3 described above differ in the execution time of the process ST2c. The execution time (2 [seconds]) of the process ST2 c in the third embodiment is 2/5 times the execution time (5 [seconds]) of the process ST2 c in the second embodiment. In this case, the removal rate of the first film M1 of the surface SFa of the first region La in the third embodiment is approximately 2/5 times the removal rate in the second embodiment.

The surface of the wafer W may be cleaned after the process ST1a and before the process ST5 (process ST1b). When the first film M1 is formed in the second region Lb, the process ST1b can be performed to remove the first film M1 from above the second region Lb. The second film M2 is not formed on the second region Lb from the start of the ALD process ST5 until all the first film M1 on the second region Lb is removed, and the first film M1 is removed from above the second region Lb Then, the second film M2 starts to be formed. Therefore, by performing the cleaning of step ST1b, the formation of the second film M2 becomes possible from the start of step ST5. Therefore, it is possible to reduce the number of executions of the process ST5 required for the second film M2 to reach the desired film thickness.

While the principles of the present invention have been illustrated and described in the preferred embodiment, it will be appreciated by those skilled in the art that the present invention can be modified in arrangement and detail without departing from such principles. The present invention is not limited to the specific configuration disclosed in the present embodiment. Therefore, we claim all modifications and changes coming from the scope of claims and the scope of the spirit thereof.

Another aspect according to the embodiment includes the following supplementary notes 1 to 4.

(Supplementary Note 1)
A method for treating an object to be treated, wherein a first film is selectively provided on the surface of the object, and ALD (atomic layer deposition) is applied to the surface of the object while removing the first film. Forming a second film.
(Supplementary Note 2)
A method of processing an object to be treated, the step of selectively forming a first film on a first region of the object to be treated, and ALD (atoms on a second region on which the first film of the object to be treated is not formed Forming a first ALD film by layer deposition), and a second ALD film is formed in the first region after the first film of the first region is removed by repeating ALD.
(Supplementary Note 3)
The method of appendix 2, wherein the thickness of the first ALD film is greater than the thickness of the second ALD film.
(Supplementary Note 4)
Preparing an object having a first region of a first material and a second region of a second material different from the first material; and etching the first region with a first plasma. A method of processing an object, comprising: forming a first film on a second region; and forming a second film by atomic layer deposition on the first region while removing the first film. .

DESCRIPTION OF SYMBOLS 10 ... Plasma processing apparatus, 12 ... Processing container, 12e ... Exhaust port, 12g ... Loading in / out, 14 ... Support part, 18a ... 1st plate, 18b ... 2nd plate, 22 ... DC power supply, 23 ... Switch, 24 ... refrigerant Flow path, 26a: piping, 26b: piping, 28: gas supply line, 30: upper electrode, 32: insulating shielding member, 34: electrode plate, 34a: gas discharge hole, 36: electrode support, 36a: gas diffusion Chamber, 36b: gas flow hole, 36c: gas inlet, 38: gas supply pipe, 40: gas source group, 42: valve group, 44: flow controller group, 46: deposit shield, 48: exhaust plate, 50 ... Exhaust system, 52 ... Exhaust pipe, 52a ... Gas introduction port, 54 ... Gate valve, 62 ... First high frequency power supply, 64 ... Second high frequency power supply, 66 ... Alignment unit, 68 ... Alignment unit, 70 ... Power supply, 82 ... gas supply , BF: film, Cnt: control unit, EL: etched layer, ELa: main surface, ELb: side surface, ELc: bottom surface, ER: area, ESC: electrostatic chuck, FR: focus ring, FW: main surface, G1 ... second gas, HP ... heater power supply, HT ... temperature control unit, La ... first area, Lb ... second area, LE ... lower electrode, LP1 ... line segment, LP1a ... line segment, LP2 ... line segment, LP2a ... line segment, LP3 ... line segment, LP4 ... line segment, Ly1 ... layer, Ly2 ... layer, MK ... mask, MKa ... side surface, MKb ... surface, M1 ... first film, M2 ... second film, MT ... method, NC: deposition portion, OP: opening, OPa: surface, P1: plasma, PD: mounting table, SFa: surface, SFb: surface, Sp: processing space, TM1: timing, TM2: timing, W: wafer.

Claims (20)

A method for treating an object to be treated, the object to be treated comprising: a layer to be etched; and a mask provided on the layer to be etched, wherein the mask has an opening reaching the layer to be etched. And the method
Anisotropically etching the layer to be etched through the opening;
Forming a film on the inner surface of the opening after execution of the step of etching the layer to be etched;
Equipped with
The step of anisotropically etching the layer to be etched generates a plasma of a first gas in a processing container of a plasma processing apparatus containing the object to be processed;
The step of forming the film comprises
A first step of supplying a second gas into the processing vessel;
A second step of purging a space in the processing container after execution of the first step;
A third step of generating a plasma of a third gas containing oxygen atoms in the processing container after execution of the second step;
A fourth step of purging a space in the processing container after execution of the third step;
Repeatedly forming a film on the surface inside the opening,
The first gas contains a carbon atom and a fluorine atom,
The second gas includes an organic-containing aminosilane-based gas,
The to-be-etched layer is a hydrophilic insulating layer containing silicon,
The first step does not generate plasma of the first gas.
How to treat an object. The first step etches the layer to be etched through the opening while adjusting the temperature of the object to be processed to be uniform over a plurality of regions of the object.
The method of claim 1. The processing vessel is provided with a first gas inlet and a second gas inlet,
The first gas inlet is provided above the object to be treated;
The second gas inlet is provided on the side of the object to be treated;
The step of anisotropically etching the layer to be etched supplies the first gas into the processing vessel from the first gas inlet, and the backflow preventing gas from the second gas inlet. Supply into the processing vessel,
The first step supplies the second gas into the processing container from the second gas inlet, and supplies a backflow preventing gas into the processing container from the first gas inlet.
In the third step, the third gas is supplied into the processing container from the first gas inlet, and the backflow prevention gas is supplied into the processing container from the second gas inlet.
The pipe connected to the first gas inlet and the pipe connected to the second gas inlet do not intersect with each other.
A method according to claim 1 or claim 2. The first gas includes a fluorocarbon gas.
The method according to any one of claims 1 to 3. The second gas comprises monoaminosilane.
The method according to any one of claims 1 to 4. The aminosilane-based gas contained in the second gas includes an aminosilane having 1 to 3 silicon atoms,
The method according to any one of claims 1 to 4. The aminosilane-based gas contained in the second gas includes an aminosilane having 1 to 3 amino groups,
The method according to any one of claims 1 to 4. A method of processing an object, comprising
Forming a first film selectively on the surface of the object to be treated;
Forming a second film by atomic layer deposition on the surface of the object while removing the first film.
Method. Said deposition is
A first step of supplying a second gas into the processing container to form an adsorption layer on the surface of the object;
A second step of purging a space in the processing container;
A third step of generating a plasma of a third gas in the processing vessel;
Contains a sequence that contains
The method of claim 8.   10. The method of claim 9, wherein the depositing further comprises the fourth step of exposing the second film to a plasma of inert gas after the third step.   The method according to claim 9, wherein in the step of forming the second film, the first film is removed by the third step or the fourth step. The second gas may be an aminosilane gas, a gas containing silicon, a gas containing titanium, a gas containing hafnium, a gas containing tantalum, a gas containing zirconium, or a gas containing organic matter Yes,
The third gas is any of a gas containing oxygen, a gas containing nitrogen, or a gas containing hydrogen.
10. The method of claim 9. The first film is formed by plasma etching.
The method according to any one of claims 8 to 12. The plasma etching is atomic layer etching,
The method of claim 13. Providing an object having a first region of a first material and a second region of a second material different from the first material;
Etching the first region with a first plasma to form a first film on the second region;
Forming a second film by atomic layer deposition on the first region while removing the first film;
A method of processing an object having: The first gas comprises a fluorocarbon gas,
The first material comprises silicon and oxygen
The second material includes any of silicon, an organic substance, or a metal,
The method of claim 15. The first gas comprises fluorohydrocarbon gas,
The first material includes any of silicon, an organic substance, or a metal,
The second material comprises silicon and nitrogen
The method of claim 15. The second film contains silicon,
The method according to any one of claims 8-17. The second film formed on the object to be treated has a plurality of film thicknesses.
The method according to any one of claims 8-18.   The method according to claim 9, wherein the first film is removed by repeating the sequence, and a second film is formed on the removed object surface.

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